Our domain_conf.* files are big enough. Not only they contain XML
parsing code, but they served as a storage of all functions whose
name is virDomain prefixed. This is just wrong as it gathers not
related functions (and modules) into one big file which is then
harder to maintain. Split virDomainObjList module into a separate
file called virdomainobjlist.[ch].
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>